Non-contact voltage detector

ABSTRACT

A voltage detector includes a cylindrical hollow body housing including an open end and a tool end. An internal circuit assembly includes a voltage sensing loop, a flashlight, and a microprocessor. The internal circuit assembly is disposed inside the cylindrical hollow body housing. The voltage sensing loop is configured to detect voltage without contacting a detected voltage, and the microprocessor is configured to control power to the flashlight via a flashlight power button independently from power to the voltage sensing loop via a voltage detector button.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is a continuation of copending U.S. patentapplication Ser. No. 15/073,939, filed Mar. 18, 2016, which claims thebenefit of U.S. Provisional Patent Application No. 62/136,125, filedMar. 20, 2015, both of which applications are incorporated herein byreference.

FIELD OF THE DISCLOSURE

The present disclosure relates to non-contact voltage detectors and,more particularly, to non-contact voltage detectors that include aflashlight.

BACKGROUND OF THE DISCLOSURE

Non-contact voltage detectors are well known in the field of electricalwork, and are used routinely by electricians, utility workers,homeowners, and others who work near electrical equipment to provide avisual and/or audible indication that an electrical component isenergized with electrical voltage. Often, the source of electricalvoltage is located in a dark place and difficult to see, such as withina wall, ceiling, or panel box. Thus, it is advantageous for anon-contact voltage detector to include both a means of illuminating thearea to be tested and a means to alert the user to the presence of apotentially dangerous voltage.

U.S. Pat. No. 6,924,605 to Chun describes a non-contact voltage detectorwith a built-in flashlight. The function of the Chun device is typicalof current non-contact voltage detector and flashlight devices. When theunit is powered on, both the flashlight and the voltage detector powerup, and when the power is turned off, or when the battery gets too weak,both the voltage detector and the flashlight shut down. The device ofChun will remain active until it is turned off, so the operator can relyon its readings during use, which can cause the battery to drainquickly. In the past, attempts have been made to prolong battery life ofnon-contact voltage detectors, for example, by using automatic powershutoff systems. Such systems, however, can shut-off the detector whilethe user believes it to be on, which may lead to inaccurate readings.

SUMMARY OF THE DISCLOSURE

The present disclosure is directed to a non-contact voltage detectorwith an integrated flashlight in which the flashlight and the voltagedetector can be powered independently. The detector further includes amicroprocessor controlled power-down system, which turns off theflashlight system and the voltage detector independently afterpredetermined and resettable time periods, and which prevents thevoltage detector from powering down while the flashlight is lit.

The device in accordance with the present disclosure addresses many ofthe issues apparent in the prior art devices. The voltage detector canbe powered on independently of the flashlight, which results in a muchlower rate of power consumption and preserves battery life. The voltagedetector automatically powers down after a predetermined time period,and the time period resets whenever voltage is detected by the tester.The flashlight can also be powered up independently of the voltagedetector, and since it will not be on at all times when the voltagedetector is in use, a much brighter and more powerful illuminationsource is used without high battery drain, and will power downautomatically after a predetermined time period. A microprocessorcontrols the power systems and automatic timeouts, and in additionensures that the voltage detector does not power down while theflashlight is on.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a detector in accordance with thedisclosure.

FIG. 2 is a top view of the detector shown in FIG. 1.

FIG. 3 is an exploded view of the detector shown in FIG. 1.

FIG. 4 is a state diagram of various functions of a detector inaccordance with the disclosure.

FIG. 5 is a state diagram of various power states and automatic powerdown programming for a detector in accordance with the disclosure.

FIG. 6 is a flow diagram of the various power states for a detector inaccordance with the disclosure.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

A preferred embodiment in accordance with the disclosure is depicted inthe accompanying figures. A detector 100 in accordance with thedisclosure is shown in FIG. 1 from a perspective view. The detector 100includes a generally cylindrical hollow body 10 with an open end cap 13and a tool end cap 15. The tool end cap 15 is generally constructed oftranslucent plastic and features a sensor protrusion 16 and atransparent flashlight lens 17. On the forward half of the cylindricalhollow body 10 and aligned with the sensor protrusion 16 is a userinterface panel 1, which rests on a raised surface 18 supported byextended walls 19 rising out of the cylindrical hollow body 10. Betweenthe cylindrical hollow body 10 and the open end cap 13 is positioned apocket clip 20 for affixing the device to various surfaces, such as ashirt pocket. During use, the user may grasp the detector 100 from thebody 10 and use fingers to operate the controls on the user interfacepanel 1, as well as receive visual feedback and signals therefrom basedon the various illumination devices disposed thereon, as discussedbelow.

FIG. 2 depicts the detector 100 as seen from the top, for example, inthe orientation the user is likely to view the detector 100 in use. Theuser interface panel 1 includes a flashlight power button 2, which isuseful to activate or deactivate the flashlight visible through the lens17, a voltage detector power button 3, which activates and deactivatesthe voltage detector functionality of the detector 100, a voltagedetector power indicator light 4, which provides a visual indication ofthe power state of the voltage detector structures, and a voltagedetector intensity readout 33, which provides a visual indication of thevoltage intensity being measured. The voltage detector power indicatorlight 4, for example, may activate when a voltage is detected.Alternatively, the voltage detector power indicator light 4 may changecolor when a voltage is detected. In the illustrated embodiment,multiple illumination devices are arranged in a series in the generalform of a bar graph such that they can be illuminated in series toprovide an indication of intensity. As shown, five indicator lightemitting diode (LED) lights: LED1 5, LED2 6, LED3 7, LED4 8 and LED5 9of the same or different colors may be used. In the illustratedembodiment, LED1 5 and LED2 6 illuminate in yellow and LED3 7, LED4 8and LED5 9 illuminate in red. The detector 100 may also include abattery indicator that indicates a battery level of the device when thedevice is activated.

FIG. 3 depicts the detector 100 in an exploded perspective view. Here,the cylindrical hollow body 10, tool end cab 15, pocket clip 20, andopen end cap 13 are shown separated. The open end cap 13 is internallythreaded and interfaces with a male thread 11 on the open end 12 of thecylindrical hollow body 10. The functional parts of the user interfacepanel 1 include a cover panel 34, a flashlight power soft touch button21, which can be used to power the flashlight functionality on and off,a voltage detector soft touch button 22 and a LED lens assembly 23. TheLED lens assembly 23 channels indication lighting from the main circuitboard 25 to the voltage detector intensity readout 33. The internalcircuit assembly 14, which would ordinarily reside inside thecylindrical hollow body 10, is instead shown beside the body 10.

The internal circuit assembly 14 is composed of a main circuit board 25,a flashlight 26, a battery holding sleeve 27, with associated batterycontacts 24, and a voltage sensing loop 28. The battery holding sleeve27 in the detector 100 is adapted to hold two AAA batteries, withelectrical connections at the battery contacts 24 and in the open endcap 13, but a different number and/or type of batteries can be used.Among other components, the main circuit board 25 includes a flashlightswitch 29, a voltage detector switch 30 and a microprocessor 31. Avoltage detection speaker 32 is located on the underside of the boardand is used to provide an audible indication of the detection ofvoltage. A volume and/or speed of succession of beeping sounds can alsobe used to audibly alert the user of the presence and intensity of avoltage detected.

FIG. 4 depicts the functional programming of the microprocessor 31 as itpertains to voltage detection. In the illustrated embodiment, detectionis segregated into six discrete Bands, but other bands or segregationschemes may be used. In the description that follows, the particularvoltage values discussed are exemplary and should not be construed aslimiting to the scope of the disclosure. In the illustrated embodiment,Band 1, indicates a condition where no voltage is detected and thedevice returns no audible or visual responses. As the detected voltageat the voltage sensing antenna or loop 28 approaches 9V, LED 1 5 beginsto flicker on and off.

In Band 2, a condition is indicated where a relatively low voltage isdetected and the device returns a, relatively slow, repeating audiblecue and illuminates a single light, LED 1. In Band 2, where the detectedvoltage at the voltage sensing loop 28 exceeds 9V but is equal to orless than 18V, LED1 5 is illuminated in yellow and the voltage detectionspeaker 32 emits an audible beep that is pulsed at a frequency of 1 Hz.As the detected voltage at the voltage sensing loop 28 approaches 19V,LED 2 6 begins to flicker on and off.

In Band 3, a condition is indicated where a relatively higher voltagethan the voltage detected in Bad 2 has been detected, and repeatingaudible cue is accelerated and more LEDs are illuminated. In theillustrated embodiment, in Band 3, where the detected voltage at thevoltage sensing loop 28 exceeds 19V but is equal to or less than 48V,LED1 5 and LED2 6 are illuminated in yellow and the voltage detectionspeaker 32 emits an audible beep that is pulsed at a frequency of 2 Hz.As the detected voltage at the voltage sensing loop 28 approaches 49V,LED 3 7 begins to flicker on and off. It is noted that LEDs 1 and 2 areyellow, but LED 3 is red, to indicate the higher voltage by color inaddition to the greater number of illuminated indicators.

In Band 4, which indicates a higher voltage condition than in Band 3,the detected voltage at the voltage sensing loop 28 exceeds 49V but isequal to or less than 85V, LED1 5 and LED2 6 are illuminated in yellowand LED3 7 is illuminated in red and the voltage detection speaker 32emits a steady beep, but a higher or different frequency can be used. Asthe detected voltage at the voltage sensing loop 28 approaches 86V, LED4 8 begins to flicker on and off.

In Band 5, which indicates a higher voltage condition than in Band 4,the detected voltage at the voltage sensing loop 28 exceeds 85V but isequal to or less than 175V, LED1 5 and LED2 6 are illuminated in yellowand LED3 7 and LED4 8 are illuminated in red and the voltage detectionspeaker 32 emits a steady audible beep, but a pulsed beep at anyfrequency higher than a lower bank may be used. As the detected voltageat the voltage sensing loop 28 approaches 176V, LED 5 9 begins toflicker on and off.

In Band 6, the highest voltage detection condition, where the detectedvoltage at the voltage sensing loop 28 exceeds 175V, LED1 5 and LED2 6are illuminated in yellow and LED3 7, LED4 8, and LED5 9 are illuminatedin red and the voltage detection speaker 32 emits a steady beep.

FIG. 5 depicts one embodiment of a functional programming of themicroprocessor 31 as it pertains to the automatic shutdown features ofthe detector 100 shown in FIG. 1. The power programming and automaticshutdown is separated into four power states or conditions for thedetector 100, which are denoted as State 1, State 2, State 3 and State4, but more or fewer conditions may be used.

In State 1, defined by the flashlight 26 and the voltage sensing loop 28both being in an unpowered state, the microprocessor 31 is also powereddown and no action occurs. In this condition, power drain from thebattery of the detector 100 is minimal or zero. Pushing the flashlightpower button 2 from State 1 puts the device into state 3. Pushing thevoltage detector button 3 from State 1 puts the device into State 2. Ina preferred embodiment, the voltage intensity readout 33 brieflydisplays an indication of the remaining battery strength when enteringState 2.

In State 2, defined by the flashlight 26 being powered off and thevoltage sensing loop 28 being powered on, the microprocessor 31 isprogrammed to automatically power the device down after 4 minutes,putting the device into State 1. The 4 minute power down timer is resetevery time the device detects a voltage, activating the voltage detectorintensity readout 33 and the voltage detection speaker 32. It should beappreciated that in this state, power consumption will be low becausethe flashlight is not activated. Pushing the flashlight power button 2from State 2 puts the device into State 4. Pushing the voltage detectorbutton 3 from State 2 puts the device into State 1.

In State 3, defined by the flashlight 26 being powered on and thevoltage sensing loop 28 being powered off, the microprocessor 31 isprogrammed to automatically power the flashlight down after 20 minutes,putting the device into State 1. In this state, the power draw from thebattery is relatively low because the voltage sensing apparatus is notpowered. Ten seconds prior to powering down the flashlight 26, thevoltage detection speaker 32 issues an audible alert, allowing the userto reset the tool in State 3 by pushing the flashlight power button 2.Pushing the flashlight power button 2 from State 3 puts the device intoState 1. Pushing the voltage detector button 3 from State 3 puts thedevice into State 4.

In State 4, defined by the flashlight 26 being powered on and thevoltage sensing loop 28 being powered on, the microprocessor 31 isprogrammed to automatically power the flashlight down after 20 minutes,putting the device into State 2. In this state, the 4-minute power downtimer for the voltage sensing loop is disabled, and now controlled bythe 20-minute flashlight power down timer. The 20-minute power downtimer is reset every time the device detects a voltage, activating thevoltage detector intensity readout 33 and the voltage detection speaker32. In this state, the power draw from the battery is maximum becauseboth the flashlight and the voltage detector circuit are active.

Ten seconds prior to powering down the flashlight 26, the voltagedetection speaker 32 issues an audible alert and the microprocessor 31alters the function of the flashlight power button 2, allowing the userto reset the tool in State 4 by pushing the flashlight power button 2.Pushing the flashlight power button 2 from State 4 puts the device intoState 2. Pushing the voltage detector button 3 from State 3 puts thedevice into State 3. If no buttons are pushed, the device times outafter 20 minutes and powers down the flashlight and voltage detector,thus entering into state 1.

A state flow diagram illustrating the various operating stages of thedetector 100 (FIG. 1) are shown in FIG. 6. The detector may operate at afirst stage 40, where the flashlight and the voltage detector circuitare both in an unpowered state. The first stage 40 is also the defaultstage the detector will assume regardless of its powered state if leftalone without user input for a preset period, as described above andalso below. From the first stage 40, the detector will enter into asecond stage 42 by user action, for example, when a voltage detectorpower button is pressed at 48. An additional press of the voltagedetector power button at the second stage will return the detector tothe first stage, again, via 48. In other words, successive presses ofthe voltage detector power button will toggle the power stage of thedetector between the first stage 40 and the second stage 42. Each timethe detector enters the second stage 42, a timer starts, for example, a4 minute timer, that counts down to an automatic power off of thedetector circuit. If the timer expires, with no user input and novoltage detection, the detector will power off the voltage detectorcircuit and revert to the first power stage 40.

Similarly, and independently, from the first stage 40, the detector willenter into a third stage 44 by user action, for example, when aflashlight power button is pressed at 50. An additional press of theflashlight power button at the third stage 44 will return the detectorto the first stage, again, via 50. In other words, successive presses ofthe flashlight power button will toggle the power stage of the detectorbetween the first stage 40 and the third stage 44. Each time thedetector enters the third stage 44, an additional timer will start, forexample, a 20 minute timer, that counts down to an automatic power offof the flashlight. If the additional timer expires, with no user input,the detector will power off the flashlight and revert to the first powerstage 40 via 52.

The detector can also assume a fourth stage 46 of power operation. Atthe fourth stage 46, both the flashlight and the voltage detectorcircuit are active. To arrive at the fourth stage 46, from the firststage 40, the detector may either pass through the second stage 42 via48, and then continue onto the fourth stage via 50 or, alternatively,pass through the third stage 44 via 50, and then continue onto thefourth stage via 48, depending on the sequence of activation of theflashlight and the voltage detection circuit by the user. When in thefourth stage 46, the detector can enter into the second stage 42 via 50,or the third stage 44 via 48, depending on user input, i.e., if the userpresses either flashlight power button (50) or the voltage detectorcircuit power button (48). Each time the detector enters the fourthstage 46, the additional timer will start, for example, a 20 minutetimer, that counts down to an automatic power off of the flashlight and,in this stage only, the voltage detector circuit, whose 4-minute timeras described in stage 2 is superseded. If the additional timer expires,with no user input, the detector will power off the flashlight, and alsothe voltage detector circuit, and revert from the fourth stage 46 to thefirst stage 40 via 52. In an alternative embodiment, a separate timermay initiate after the additional timer, which powers down theflashlight, expires. The separate time, which can be a 4-minute timer,can extend the powered state of the voltage detection circuits beyondthe power off time of the flashlight, such that voltage can be detectedfor a longer period. In such alternative embodiment, the device maytransition from stage 4 to stage 2 and then, ultimately if there is nouser input, to stage 1. To conserve power, when the microprocessordetects a low battery level, the voltage detector may be configured toenter stage 2 but not stage 3 or stage 4.

All references, including publications, patent applications, andpatents, cited herein are hereby incorporated by reference to the sameextent as if each reference were individually and specifically indicatedto be incorporated by reference and were set forth in its entiretyherein.

The use of the terms “a” and “an” and “the” and “at least one” andsimilar referents in the context of describing the invention (especiallyin the context of the following claims) are to be construed to coverboth the singular and the plural, unless otherwise indicated herein orclearly contradicted by context. The use of the term “at least one”followed by a list of one or more items (for example, “at least one of Aand B”) is to be construed to mean one item selected from the listeditems (A or B) or any combination of two or more of the listed items (Aand B), unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. Recitation of ranges of valuesherein are merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. All methodsdescribed herein can be performed in any suitable order unless otherwiseindicated herein or otherwise clearly contradicted by context. The useof any and all examples, or exemplary language (e.g., “such as”)provided herein, is intended merely to better illuminate the inventionand does not pose a limitation on the scope of the invention unlessotherwise claimed. No language in the specification should be construedas indicating any non-claimed element as essential to the practice ofthe invention.

Preferred embodiments of this invention are described herein, includingthe best mode known to the inventors for carrying out the invention.Variations of those preferred embodiments may become apparent to thoseof ordinary skill in the art upon reading the foregoing description. Theinventors expect skilled artisans to employ such variations asappropriate, and the inventors intend for the invention to be practicedotherwise than as specifically described herein. Accordingly, thisinvention includes all modifications and equivalents of the subjectmatter recited in the claims appended hereto as permitted by applicablelaw. Moreover, any combination of the above-described elements in allpossible variations thereof is encompassed by the invention unlessotherwise indicated herein or otherwise clearly contradicted by context.

It will be appreciated that the foregoing description provides examplesof the disclosed system and technique. However, it is contemplated thatother implementations of the disclosure may differ in detail from theforegoing examples. All references to the disclosure or examples thereofare intended to reference the particular example being discussed at thatpoint and are not intended to imply any limitation as to the scope ofthe disclosure more generally. All language of distinction anddisparagement with respect to certain features is intended to indicate alack of preference for those features, but not to exclude such from thescope of the disclosure entirely unless otherwise indicated.

Recitation of ranges of values, or values, herein are merely intended toserve as a shorthand method of referring individually to each separatevalue falling within the range, unless otherwise indicated herein, andeach separate value is incorporated into the specification as if it wereindividually recited herein. All methods described herein can beperformed in any suitable order unless otherwise indicated herein orotherwise clearly contradicted by context.

I claim:
 1. A control system for a voltage detector having a voltagedetector circuit and a flashlight circuit comprising: a first stage, thefirst stage corresponding with a deactivated voltage detector circuitand a deactivated flashlight circuit; a second stage, the second stagecorresponding with an activated voltage detector circuit and adeactivated flashlight circuit; a third stage, the third stagecorresponding with a deactivated voltage detector circuit and anactivated flashlight circuit; and a fourth stage, the fourth stagecorresponding with an activated voltage detector circuit and anactivated flashlight circuit, wherein the first stage is a defaultstage, and wherein: user action is required to transition from the firststage to any one of the second stage, the third stage, and the fourthstage, and user action is required to transition from the second stageto the fourth stage.
 2. The control system of claim 1, wherein thevoltage detector automatically enters the first stage from the secondstage after a first predetermined period of time, and wherein thevoltage detector automatically enters the first stage from the thirdstage after a second predetermined period of time, the voltage detectorissuing an audible alert via a voltage detection speaker before thesecond predetermined period of time expires.
 3. The control system ofclaim 2, wherein the voltage detector automatically enters the firststage from the fourth stage after the second predetermined period oftime expires.
 4. The control system of claim 2, wherein the secondpredetermined period of time is greater than the first predeterminedperiod of time.
 5. The control system of claim 1, wherein a timer startswhen the voltage detector enters at least one of the second stage, thethird stage, and the fourth stage.
 6. The control system of claim 5,wherein if the voltage detector is in at least one of the second stageand the fourth stage, the timer resets when a voltage is detected. 7.The control system of claim 1, wherein when the microprocessor detects alow battery level, the voltage detector is able to enter the secondstage but prevented from entering the third stage or the fourth stage.